Garmin GNS 480TM GPS Receiver User Manual


 
18
Advanced Operation
Nav Mode
Listening to the Audio channel
The audio for the active Nav channel is toggled between modes using the ID button. The
annunciator above the button will light while Nav audio is activated, and the detected audio
signal will be sent to the Nav audio output circuit. Nav audio may also be mixed with the
Com audio output, if selected in the System mode. When you are monitoring a VOR, Nav
audio is suspended.
There are three modes for the Nav audio. Press the ID button to start the ID mode.
“IDENT” will be displayed for three seconds. The Morse code tones sent over the VOR/Local-
izer channels will be heard.
If the ID button is pressed a second time. “
VOICE
” will be displayed for three seconds.
The Morse code tone volume will be reduced so you can hear the voice transmission more
clearly.
Press ID again to turn the audio and ID annunciator off.
The last audio output selection is kept in memory until you change it, even when the
SL30 is powered off. Using this feature, you may leave the audio enabled and then control it
by an external audio panel.
Automatic Morse Code Decode/Display
The Morse code identifier will not be available until two messages have been successfully
received, which may take from 15-60 seconds depending on conditions. When no voice is
present on the station, the Morse code identifier is decoded correctly at least 99.5% of the
time. If the station is transmitting voice along with the Morse Code identifier, the probability
of the SL30 to decode the identifier drops to 95%. Voice or poor reception (such as the sta-
tion is far away) may delay or inhibit the automatic decode function.